Tube socket



Ap 2 1941- M. ALDEN TUBE SOCKET Filed Aug. 14, 1940 INVENTOR I flflZzlazp Am Patented Apr. 22, 1 941 UNITED STATES PATENT OFFICE TUBE SOCKET Milton Alden, Brockton, Mass.

Application'August 14, 1940, Serial No. 352,493 8 Claims. 21. 173-328) My invention relates to lamp sockets and more particularly to those used in pairs for receiving the ends of a tubular lamp, provided with double prongs, spaced apart from one another, upon each end.

This invention embodies certain features of the formof construction shown in my co-peuding application Serial No. 333,086.

More particularly, this invention relates to sockets of the type wherein the insertion of the lamp is accomplished by pushing the prongs into a slotted rotary member, which member is then rotated in such fashion as to bring the prongs into contact with stationary connection members located in the socket body and attached to external conductors for supplying energy to the lamp.

One object of this invention is to provide a socket construction for holding one end of a double ended lamp, such as a tubular lamp of the fluorescent type, having a plurality of prongs upon each end thereof.

Another object is to provide a structure of this character which shall be simple, cheap to manufacture and safe and easy to operate.

A special object of this invention is to provide a socket of this type wherein the lamp prongs may be easily inserted and guided into position before rotation of the lamp.

A yet further object is to provide means whereby the insertion of the prongs may be determined, even though the socket be not visible to the person inserting the lamp thereinto.

Yet another purpose of this invention is to afford in a structure of the type described, means whereby an attempt at the rotation of the socket rotor before the prongs of the lamp have been firmly seated therewithin will not give rise to undue strain upon the prongs of the lamp, or upon the parts of the socket, such as might cause breakage of the socket, or of the lamp end or body.

. Another purpose is to provide a socket wherein a change of resistance to insertion of tube prongs thereintolwill afford an indication of the final seating of the tube into place.

Other purposes and advantages of my invention will be apparent from the description'here inafter given.

Fig. 1 is a view in front elevation of a socket embodying one form of my invention, the tube prongs being shown in position therewithin, but out of contact. 7

Fig. 2 is a view in elevation from the rear; of the structure shown in Fig. 1, with tube rotated to contact position and the back plate removed.

Fig. 3 is a side elevation. partly in section.

Fig. 4 is an end view of the socket.

Fig. 5 is an end view with the insulation broken away so as to show a tube prong in position therewithin.

Fig. 6 is a view in elevation of the upper portion of a variant form of socket according to this invention, illustrating the guidance of tube prongs into position.

Fig. 'l'is a view of one mode of construction of the rotor of a socket, the parts being separated for purposes of clarity of illustration.

Fig. 8 is a view of another mode of construction of the rotor in a one piece element.

Referring now more particularly to Figs. 1, 2 and 3, a body I, of suitable insulating material is provided with a screw slot l' for mounting purposes and also with a rotor, also formed of insulating material, and comprising two discrete sections, 2 and 3. These may be formed as shown in Fig. '1, with flat upper surfaces 4, rims 5 which are mounted in the circular opening of 'thebody, wedge shaped portions 6 to engage the socket springs, and smooth portions 1, which last serve in conjunction with one another to form a cylindrical bearing. A portion 1' is cut away, so that when placed together, a slot is formed between the two portions.

Stationary spring contacts 8 are secured to a suitable insulating part 9, of the body of the socket, and are each provided with a connecting screw Ill, of any suitable type for the reception of an external wire. The upper portion ll of each spring is bent so as to form a prong-receiving recess. Tube prongs I2 are shown in position therein. These particular portions of my socket may be formed in accordance with the avoid the exposure of live parts to possible human contact therewith. The edges of the rotor sections may be cut away as shown at ll, so

that the tube prongs may be inserted and lie therewithin, as shown in Fig. 1, or may be shaped somewhat diilerently, as shown in Fig. 6.

Referring now additionally to Figs. 4 and 5,

I it will be seen that the upper part of the body is provided with inclined guides l5, which are Joined by a back portion I. These guides cause thetubeprongstobedirectedintoaslot ",and

' therethrough into the center oi the rotor. The

back ll may slope inwardly toward the base so as iurther to guide the tube prongs longitudinally.

Preierably this slot I1 is reduced in its vertical dimension as shown in Fig. 6 until it becomes virtually imposible tor the prongs oi a tube when rotated to exert lateral pressure upon the walls .oi the slot. This action may be promoted by rounding oi! the edges l'l oi the slot. Prei'erably the radius oi curvature oi the edges I!" is less than the radius oi the tube prongs. Under these conditions the prongs will be guided into the rotor, and any torque exerted upon the tube cannot cause the prongs to Jam in the slot, or cause the prongs to be bent or loosened by any lateral pressure thereupon, since the sloping walls and shaped edges oi the slot oi the iorm oi Fig. 6 will cause the tube to beeither drawn down into position within the rotor, or else ii it has not been inserted iar enough, will cause it to be ejected in an upward direction irom the socket. The dotted circle I! oi Fig. 6 shows the end oi the tube as it is being inserted into the socket. Fig. 6 likewise shows how the two halves of the rotor will separate slightly as the prong enters one end oi the slotted portion thereof. After both prongs have passed into the cut-away portions ll oi the rotor, the two halves will again assume substantially the position shown in Fig. 1.-

Instead of making the rotor in two wholly separate sections, a single element, as shown in Fig.

8, may be provided. In this case, the insulating material is chosen so as to have suflicient elasticity so that the prongs will slightly iorce apart the walls of the slot 1" notwithstanding that the bearing portion in this case is constituted by a single solid portion IS. The notches or ends ll of the slot are made just wide enough to receive the tube prongs and the slot at l" is made narrower than the diameter oi the prongs so thatwhen the tube prongs are inserted, resistance to insertion is met which instantly ceases when the prong reaches the bottom of the slot at H. I

may provide a slight depression in the central part oi the slot. When a tube prong is inserted, it will first seat itself in this depression, and then pass to its ultimate resting-place in notch l4. Thus a tube will snap into place in two steps, which action will serve as a guide to the person inserting the same, even though the socket be not visible to him at the time of such insertion.

I claim:

1. A tube socket including abody oi insulating material, a slotted carrier rotatably mounted within said body and having a groove affording entry to the prongs of a tube base within the groove of said carrier and also allowing said prongs when inserted to describe arcs of rota.- tion when said carrier is rotated, spring contacts mounted within said body and making contact with said prongs, respectively, upon the rotation oi said carrier, said carrier being laterally expansible upon the insertion in the groove of a tube prong and said body being also provided with an entrance slit located in one edge thereof, through which slot said prongs can enter to seat within said groove in said carrier.

2. A socket 101- the reception oi a twin-pronged base including a body portion having in one edge thereoi a slit ior the passage therethrough oi the tube prongs and also having a plurality oi con- 75 said slitted member, whereby the prongs or a 4 taetsiorrecelvingsaidpronnarotorhavingtwo spacedsectionsarrangedrespectivelyupmoppositesidesoithellitandyieldablemeanliorcing saidaectionstowardeachothenwherebythein- ,sertionoiatubeprongthroughthellitinsaid body into one end of the space between said section: will cause said sections to separate sumciently to admit the passage therewithinoi said tube prong.

3. A socket ior the reception at a twin-pronged tube base including an elongated body oi insulating material having at one end thereoi a central entrance slit with shoulders on either side thereoi, a grooved rotary member mounted-in the same end oi said body. the entrance slit and the groovein said rotor at a predetermined angular position oi the rotor iorrning a continuous passageway ior the entrance oi. the tube prongs into said rotor, and contact springs ior engagement with said prongs located upon opposite sides oi said rotor, said shoulders extending at least as iar irom said entrance slot as the distance between the tube prongs, whereby the entrance oi one prong into said entrance slit prevents the other prong from passing over the outer edge oi r one oi said shoulders.

4. In a socket ior the reception oi,a twinpronged tube base oi the type using a rotor to receive and guide the tube prongs into contactmaking position, a rotor having two parts with a slot therebetween tor the passage oi tube prongs, means ior resiliently urging said parts towards one another so as to require the separation oi the parts when said prongs enter said rotor, and

contact-making means located upon opposite sides oi said rotor ior making contact with the respective tube prongs when said rotor is turned about its axis.

5. A socket for a two pronged lamp comprising a body oi insulating material with a chamber therein, a pair oi spaced spring contact arms mounted in the chamber, said body having a circular opening in one iace and a slot leading to the space between said contact arms, an insulating carrier mounted to rotate in said opening and composed oi two parts with a diametrical slot between them, the two parts being movable toward and irom each other, said two carrier parts having angular portions embraced by said spring contact arms. i

6. In a rotor type socket, a body of insulation. a slitted rotor ior the reception oi tube prongs and rotatable within said body, said body having spaced prong receiving contacts on opposite sides .of said rotor and likewise being iormed with aslit passing irom one lateral suriaceoi said body tothe edge oi said rotor, said slit having a longitudinal extension small compared with the diameter oi a tube prong, and said body being provided with smoothly inclined guiding suriaces leading irom a lateral wall thereof to the beginning oi saidslit, whereby a tube prong will be trance slot being approximately semi-cylindrical tube being inserted into said socket will be guided longitudinally into said slitted member,

8. A socket for the reception of a twin-pronged 4 with a radius of curvature so small as to elimitube base including an elongated body of insulatand rotated within said body, the edges of said ennate any substantial abutment fora tube prong and said shoulders extending at least as far from said entrance slot as the distance between the contact springs when engaged by the tube prongs, whereby the entrance of one prong into said entrance slot prevents the other prong from passing over the outer edge of one of said shoulders.

MILTON ALDEN. 

